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First Lady Michelle Obama criticized Donald Trump's complaints about a microphone issue

She said individuals who are tweeting at 3 a.m. should not have their fingers on nuclear codes

CNN  — 

First lady Michelle Obama once again tore into Donald Trump while campaigning for Hillary Clinton, going after the Republican nominee for tweeting at 3 a.m. and for Trump’s microphone issues at the first presidential debate.

“When it comes to the qualifications that we should demand of our president, to start with we need someone who will take the job seriously,” Obama said in Charlotte, North Carolina – the first of two campaign stops in the state Tuesday.

The first lady – who never mentioned the Republican nominee by name – also defended Clinton’s stamina and toughness, which have been brought into question by Trump.

“When she gets knocked down, she doesn’t complain, she doesn’t cry foul,” the first lady said while repeatedly tapping on her microphone in reference to Trump, claiming his debate microphone last week was “defective.”

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“We also need someone who is steady and measured because when making life or death, war or peace decisions, a president can’t just pop off or lash out irrationally,” she said. “And I think we can all agree that someone who’s roaming around at 3 a.m. tweeting should not have their fingers on the nuclear codes.”

Obama was referring to a series of tweets that Trump sent in the middle of the night, disparaging a former beauty queen who has publicly taken issue with the billionaire businessman’s comments toward her.

Trump called his microphone in the first debate “defective,” and the following Friday, the Commission on Presidential Debates in a statement said that “there were issues regarding Donald Trump’s audio that affected the sound level in the debate hall.”